Mechanical dishwasher



Dec. 31, 1929. I F. A. WALKER uEnANicAL DiSI-IWASHER Filed July 14. 1926 1 VENTOR. J, ATT%NEYS.

35 acted. upon by the ,impe

Patented Dec. 31, 1929 umrro STATES PATENT orrlca FORREST A. WALKER, OI SYRACUSE, NEW YORK, ASSIGNOR TO WALKER DISHWASHER CORPORATION, OF SYRACUSE, NEW YORK, A. CORPORATION OF NEW YORK p MECHANICAL msnwasrma Application filed July 14,

tor driven rotary. impeller, the water 'being brought into contact with the dishes in a superimposed open-work tray orbasket.

In dishwashers of this type the bottom of the vat is preferably made 1n the form of a hopper -or inverted cone and the level 'of the-amount of the washing fluid is limited by the overflow to a level between the apex 1 and top of the conical bottom, the ob ect of u which is three-fold, ajz, first, to conserve the water, second, to prevent overload upon the impelle'rand its actuating motor, third, 2 to enable practically theentire body of wa-4 ter to be displaced upwardly by a centrifugal force due to the rotation of the impeller -and to continually maintain this upward displacement with a whirling motion as the q fluid falls back into the ,conical bottom thereby establishing a continuous impact of thewashing fluid against the dishes in at least three directions, upwardly, downward ly and circumferentially.

Under these conditions. the dishes are thoroughly and expeditiously cleansed with a minimum donsumptionof water-and pow-a er and after drawing off thewashing fluid a clean rinsing fluid ma lfiar in the same manner as the washing fluid] for rinsing the dishes which after stopping the moto g impeller driven thereby ma 'be allowed 0 1-9- for supportiiig an electric motor as drain and dry in the ba ets before removal from the vat. I a Y The basket or baskets withthe cleansed and dried dishes therein may then be re-- moved-By hand to any desirable locality for storing. I p

The-main object of the present invention is to construct the impeller in such manner 9 asito increase therapidity of upward displacement and 'whirh'ng motion of the water with'less (power-than 'hasheretofore been 3 practised and thereby to greatly expedite be introduced and 1926; Serial No. 122,277,

the thorough washing and cleansing of the dishes in the basket or baskets and incidentally to increase the output of the work.

Other objects and uses relating to specific parts of the machine will be brought out in ,4

the following description. In the drawings:

Figure 1 is a horizontal sectional view of the vat showing the impellerin top plan.

Figure 2 is a vertical sectional view ofthe same takenin the plane of line 2-2, Fi re 1, the upper portion of the vat being roken away.

Figure3 is a side elevation of the detached I impeller.

As illustrated, the machine comprises a.

vat'1-'- mounted upon suitable supporting legs --2 and provided with abottom' hopper 3 in the form of an inverted cone having its upper smarginal edge returned downwardly and secured to the inner walls ably made of non corrodable sheet metal.-

The bushing 4- extends some distance below the apex ofthe' bottom-3 for receiving-a cast metal section 6- and clamping nut--7 and also serves to receive a coupling member --8 and a post -10- in a manner presently described;

\ The hub of the cast metal section 6 is itli the axis of the-vat and pro- 'ti'ght'loint w th, said vat being prefer applied to the under side of the apex of the conlcal bottom +3 and is secured in place by the nut '-7 engaging the externally threaded portion of the bushing 4- Figure 2. i T

' The conical bottom -3-- is also provided near its apex with an outlet opening just at one side of the. flange -5 of the bushing --4-, the walls of the-oulet opening be- I lar bushing 4.-- and some distance beyond the lower and upper ends thereof and is'clamped to said bushing a ainst relative rotation by means of the coup ing 8-- and packing --'8 which latter is seated in an annular groove in the periphery of the post 9- and in addition to supporting the post against vertical movement relatively to said bushing also forms a water-tight joint with the bushing. a

A cross bar or plate 14 is secured by brazing or otherwise to the lower end of the post 9 and is clamped to the upper end of the motor -10 by means of bolts -15'- and spacing members 16 for supporting the motor endwise vertically with the axis of its armature shaft co-axial with the axis of the vet.

The pate --14- and motor +10 are placed against lateral vibration by braces -17 having their lower ends secured by the bolts 15 to the plate 14 and their upper ends together with the upper ends of 5 the legs 2 firmly secured to the marginal rim of the bottom 3- and lower end of the vat -l by bolts -18 which also clamp the rim of the bottom 3 to the lower ends of the side walls of the'vat as shown in Fig-' ure 2.

The upper end of the post 9- extends above the upper end of the conical bottom -3- of the vat and therefore above the normal water level as --aand serves as a journal bearing for the armature shaft 19- of the motor 10.

That is the motor shaft extends vertically entirely through and above the tubular post -9,- so-axial with the axis of the vat 1- and hasits upper end reduced and threaded fog receiving and supporting an impeller v This impeller comprises a central vertical- 1y elongated hub '-21 and spiral blades '-22- rigidly secured to the hub in ver-' The interior diameter of the hub 21- is about the same as the external diameter of the post --9 with just sufficient clearance to allow the impeller to rotate freely relatively to the post, said hub bein extended some distance above and below t e normal water 'level --w and when secured upon the upper liability of leakage of the washing fluid downwardly along the shaft and throu h the post.

In the present machine two 0 the blades 2Q are employed on the hub of the sleeve 21- and each blade extends spirally around the sleeve to incline from the to downwardly and circumferentially in the dlrection of rotati on of the motor shaft and impeller carried thereby.

The bottoms of the blades 22 are substanti'ally fiat radially while the marginal edges thereof are substantially cylindrical and are provided with upturned flanges 22' extending from end,toend thereof but gradually reduced in verticaldepth at their ends. V '1 The object in making the bottoms of the blades substantially flat radially and spirally inclined upwardly from their lower ends is to gradually lift the washing fluid as the impeller is rotated with a minimum resistance of the water while the flanges ---22- serve to resist the centr ifugal displacement of the water from the bottoms of the blades and also to deflect the water upwardly due to its centrifugal motion. i a r In other words, the bottoms of the blades constitute circular inclined planes which are d'sposed circumferentially at relatively sharp a ute angles to a horizontal plane passing through said particular portion thereof so as to effect a gradual but positive lifting of the Y water from the bottom of the vat upwardly and ag inst any dishes which may be'supported n open-work trays some distance above the impeller, the dishes and support therefor being omitted. A

The securementof the impeller -20 directly to the'motor shaft -16- assures the rotation of the, impeller at the same rate of speed as the motor shaft which speed is sufficient to cause the impeller blgdes to displace the water from the conica the vat upwardly and circumferentially with awhirling motion tending to draw the entire body of water from the center toward the periphery of the vat but owing to the circumferential flanges 22' upon and around the marginal edges of the bottoms of the blades this centrifugal motiondirectly from the bot-.

toms of the ladesis rotated by the flanges --22' against which the water is thrown by centrifugal force and by which it is deflected upwardly and laterally in the form of an inverted cone, the outlines of which are indicated by dotted lines b, Figure 2, so that bottom of the upward displacement of practically the entire body of the water previously within movement as it leaves the impeller blades thereby assisting in distributing the upward whirling motion of the water throughout the interior area of the vat from the bottom to the top thereof. 1

As the water the vat it is immediately picked up and thrown upwardly again by the impeller, this operation being practicall continuous to produce the three motions of t 1e water previously mentioned, namely the upward motion, the downward motion and the circular J ually reducing 1n=rad1al-w1dth from their centrifugal motion, all of which contributes to the expeditious and thorough cleansing of the dishes with a minimum amount of water and a relativelysmall consumption of the current for the motor.

The lower end of the motor shaft is stepped upon a ball-bearing 25 in the lower end of the motor case to take the downward thrust conical bottom provided with a tubular post falls back into the bottom of secured in said opening and extending some distance above the bottom of the rece tacle, a shaft extending from the undersi e upwardly through and above. the tubular post, means for rotating the shaft; and an impeller secured to the upper end of the shaft above the post and provided with xa spiral blade (intending some distance ,above and below the upper end of the post and gradually reduced in radial width from. its lower end to its upper end.

4.. In a mechanical and washing fluid having an inverted conical bottom provided with an opening in the apex thereof, a tubular post secured in said opening and extended upwardly some .dis-

,tance' above said apex, a shaft extendingh'om the underside upwardly through and above the'post, means for rotating the shaft, and an impeller having a hub surrounding the post and extended some distance below and above the top of the post and having its upper end secured to the shaft, saidhub being provided with a plurality of spiral blades pro- 'ecting from the periphery t ereof and gradhand this 26th day of June, 1926.

FORREST A. WALKER.

of saidfshaft due to the lifting load upon, the impeller, said ball-bearing being ad ustable extended upwardly from the apex thereof,

a shaft extending from the underside up.-,

- wardly through and above the post, means for rotating the shaft, an impeller having a hub surrounding the. post and havmg its upper end secured to the shaft above the post, said hub being provided with a spiral blade extending from a level some distance below the top of the post to a levelsome distance above the top of the post, said blade being gradually reduced in radial width from bottom to top. I

3. Ina mechanical dishwasher of the .charactor described, a receptacle for the dishes and washing fluid having an opening een-' trally in" the bottom thereof,a tubular post dishwasher of the .char- I acter described, a receptacle for the dishes 

